His first postdoctoral position was working with Prof. Tony Thomas in the
Theoretical Physics group at the University
of Adelaide from 1984-86.

Following this he moved to the U.S. to work with the Nuclear Theory group in the
Department of Physics at the University of Washington
in Seattle, where he was a postdoctoral research associate for three years from 1986-89. The
department was also host to the National Institute
for Nuclear Theory supported by the (U.S.) Department of Energy.

In August 1989 he began work as an Assistant Professor at
Florida State University in Tallahassee, Florida, where he
had a joint appointment in the Department
of Physics and in the Supercomputer Computations Research Institute (SCRI).

He was Chair of the Organizing Committee for the 14th National Congress of the Australian
Institute of Physics (AIP2000) in December 2000, which had over 680 registered participants.

He was founding Director of the South Australian Partnership for
Advanced Computing (SAPAC), which was an unincorporated joint
venture of the three South Australian universities: the University of
Adelaide, Flinders University, and the University of South Australia.
SAPAC commenced operations in September 2002.
SAPAC has now evolved into eResearch SA.

He was also Deputy Director of the National Institute for Theoretical Physics (NITP).
He was Deputy Head of the Department of Physics and Mathematical Physics from 2000-02.

He was promoted to the position of Professor in the Department of Physics and Mathematical
Physics in July 2003.

He was appointed Executive Director of the Australian Research Collaboration Service (ARCS)
in December 2007 to September 2011. ARCS was a four-year project delivering eResearch infrastructure
to the national research community and was funded with $22.5 million by the Australian government.

He served on the Australian Research Council College from 2008-09 and has been reappointed for the
period 2012-14.